What to Expect When You’re Changing the DB_UNIQUE_NAME

I recently had to change the db_unique_name of a database to make it jive with our typical database/DataGuard naming policy of appending the datacenter location. For the sake of this post let's say it was changed from ORCL to ORCL_NYC, since this database is in our fictional New York City datacenter.

I did a quick set of tests and thought I'd share the findings to save anyone any unpleasant surprises. Here are the things to (more...)

Oracle Direct NFS and Infiniband: A Less-Than-Perfect Match

Readers of an earlier post on this blog will know about my latest forays into the world of Direct NFS. Part of that means stumbling over configuration hiccups or slamming into brick walls when you find new bugs.

To quickly re-set the table, my organization purchased the Oracle ZFS Storage Appliance (ZFSSA) 7420. Oracle sold us on the Infiniband connectivity as a way to make a possible future transition to Exadata easier. However the pre-sales (more...)

The Danger of Moving Incrementally Updated Datafile Copies

When I sat down at my desk yesterday morning I was greeted with some disturbing email alerts notifying me that one of the NFS mounts on my standby database host was full. This was the NFS mount that held an image copy of my database that is updated daily from an incremental backup. The concept and an example can be found in the documentation. With a 25Tb database, waiting to restore from backups is not (more...)

ZFSSA EM12c Plugin Pro-Tip

When adding ZFSSA targets to #EM12c, be sure to uncheck "kiosk user" for the oracle_agent user in ZFSSA. Doc ID 1609846.1

https://twitter.com/dtseiler/status/428210917155692544

Upgrading EM12c to 12.1.0.3: Active Directory Authentication Quirks

We recently upgraded our EM12c 12.1.0.2 installation to 12.1.0.3. This service was configured to authenticate logins against our Active Directory server via LDAP. However, after upgrading we found that authentication stopped working, even after recreating the Active Directory Authenticator (as required). I could see the list of users from AD, but could not authenticate them in EM!

In this post I'm going to share what we did to diagnose (more...)

shutdown abort: Not always "fine"

When I started out as an Oracle DBA on Oracle 7.3, nearly everyone would tell you to avoid doing a "shutdown abort" if at all possible since it leaves the database open to possible corruptions. In the years and versions since, that thinking has softened greatly, to the point (more...)

Oracle Direct NFS (and Linux Routing) … for Dummies!

When I started my current role a few months ago, I was very interested to learn that direction had been set to migrate away from ASM and onto NFS storage that had some read flash cache in front of it. I'm not the world's biggest fan of ASM and the (more...)